1. Field of Invention
The present invention relates to a gasket for sealing between a box type body for accommodating an electronic device, particularly a hard disc drive, and a cover, and a structure for sealing between two members by using the gasket.
2. Description of the Conventional Art
In conventional devices, a box type body for accommodating a hard disc drive used for an electronic device employs a casting. However, there is a tendency in recent years that a contact surface of the gasket for sealing between the box type body and a cover and a width of the gasket have been narrowed, in accordance with a downsizing of electronic devices and the hard disc drive used therein.
It is proposed that a sealing performance between a box type body and a gasket is increased by setting a cross sectional shape of the gasket to a shape of the device constituted by a base portion and a protruding portion. Further, a shape is specifically a rate between a width and a height of the gasket or the like.
However, it is required to reduce a space of an installation surface of the gasket and narrow the gasket itself in accordance with a further downsizing of electronic devices and the hard disc drive used therein. In addition, there is the necessity of switching the box type body from the conventional casting to a downsized thin plate product of a sheet metal press molding. As a result, a width of an end surface of a peripheral wall of the box type body with which the gasket is brought into contact is extremely limited. There is a risk that a lip portion is not normally brought into contact with the box type body in the gasket having the shape mentioned above, and there is fear that sealing performance is lowered.
Further, when the cover is made from the thin plate, an excessive deflection deformation is generated in the cover between fixing screws due to a gasket repulsion load at a time of assembling. There is a problem that the sealing performance is lowered by a contact failure between the gasket and the sealed surface at a position where the deflection deformation of the cover is the most.
Patent Document 1: Japanese Unexamined Patent Publication No. 2004-036630